﻿// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System.ComponentModel;
using System.ComponentModel.Design.Serialization;
using System.Drawing;
using System.Windows.Forms.Layout;

namespace System.Windows.Forms;

[ProvideProperty("ColumnSpan", typeof(Control))]
[ProvideProperty("RowSpan", typeof(Control))]
[ProvideProperty("Row", typeof(Control))]
[ProvideProperty("Column", typeof(Control))]
[ProvideProperty("CellPosition", typeof(Control))]
[DefaultProperty(nameof(ColumnCount))]
[DesignerSerializer($"System.Windows.Forms.Design.TableLayoutPanelCodeDomSerializer, {AssemblyRef.SystemDesign}",
    $"System.ComponentModel.Design.Serialization.CodeDomSerializer, {AssemblyRef.SystemDesign}")]
[Docking(DockingBehavior.Never)]
[Designer($"System.Windows.Forms.Design.TableLayoutPanelDesigner, {AssemblyRef.SystemDesign}")]
[SRDescription(nameof(SR.DescriptionTableLayoutPanel))]
public class TableLayoutPanel : Panel, IExtenderProvider
{
    private readonly TableLayoutSettings _tableLayoutSettings;
    private static readonly object s_eventCellPaint = new();

    public TableLayoutPanel()
    {
        _tableLayoutSettings = TableLayout.CreateSettings(this);
    }

    public override LayoutEngine LayoutEngine => TableLayout.Instance;

    [Browsable(false)]
    [EditorBrowsable(EditorBrowsableState.Never)]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
    public TableLayoutSettings LayoutSettings
    {
        get => _tableLayoutSettings;
        set
        {
            if (value is not null && value.IsStub)
            {
                // WINRES only scenario.
                // we only support table layout settings that have been created from a type converter.
                // this is here for localization (WinRes) support.
                using (new LayoutTransaction(this, this, PropertyNames.LayoutSettings))
                {
                    // apply RowStyles, ColumnStyles, Row & Column assignments.
                    _tableLayoutSettings.ApplySettings(value);
                }
            }
            else
            {
                throw new NotSupportedException(SR.TableLayoutSettingSettingsIsNotSupported);
            }
        }
    }

    [Browsable(false)]
    [EditorBrowsable(EditorBrowsableState.Never)]
    [Localizable(true)]
    public new BorderStyle BorderStyle
    {
        get => base.BorderStyle;
        set
        {
            base.BorderStyle = value;
            Debug.Assert(BorderStyle == value, "BorderStyle should be the same as we set it");
        }
    }

    [DefaultValue(TableLayoutPanelCellBorderStyle.None)]
    [SRCategory(nameof(SR.CatAppearance))]
    [SRDescription(nameof(SR.TableLayoutPanelCellBorderStyleDescr))]
    [Localizable(true)]
    public TableLayoutPanelCellBorderStyle CellBorderStyle
    {
        get { return _tableLayoutSettings.CellBorderStyle; }
        set
        {
            _tableLayoutSettings.CellBorderStyle = value;

            // PERF: don't turn on ResizeRedraw unless we know we need it.
            if (value != TableLayoutPanelCellBorderStyle.None)
            {
                SetStyle(ControlStyles.ResizeRedraw, true);
            }

            Invalidate();
            Debug.Assert(CellBorderStyle == value, "CellBorderStyle should be the same as we set it");
        }
    }

    private int CellBorderWidth => _tableLayoutSettings.CellBorderWidth;

    [Browsable(false)]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    [SRDescription(nameof(SR.ControlControlsDescr))]
    public new TableLayoutControlCollection Controls => (TableLayoutControlCollection)base.Controls;

    /// <summary>
    ///  This sets the maximum number of columns allowed on this table instead of allocating
    ///  actual spaces for these columns. So it is OK to set ColumnCount to Int32.MaxValue without
    ///  causing out of memory exception
    /// </summary>
    [SRDescription(nameof(SR.GridPanelColumnsDescr))]
    [SRCategory(nameof(SR.CatLayout))]
    [DefaultValue(0)]
    [Localizable(true)]
    public int ColumnCount
    {
        get => _tableLayoutSettings.ColumnCount;
        set
        {
            _tableLayoutSettings.ColumnCount = value;
            Debug.Assert(ColumnCount == value, "ColumnCount should be the same as we set it");
        }
    }

    /// <summary>
    ///  Specifies if a TableLayoutPanel will gain additional rows or columns once its existing cells
    ///  become full.  If the value is 'FixedSize' then the TableLayoutPanel will throw an exception
    ///  when the TableLayoutPanel is over-filled.
    /// </summary>
    [SRDescription(nameof(SR.TableLayoutPanelGrowStyleDescr))]
    [SRCategory(nameof(SR.CatLayout))]
    [DefaultValue(TableLayoutPanelGrowStyle.AddRows)]
    public TableLayoutPanelGrowStyle GrowStyle
    {
        get => _tableLayoutSettings.GrowStyle;
        set => _tableLayoutSettings.GrowStyle = value;
    }

    /// <summary>
    ///  This sets the maximum number of rows allowed on this table instead of allocating
    ///  actual spaces for these rows. So it is OK to set RowCount to Int32.MaxValue without
    ///  causing out of memory exception
    /// </summary>
    [SRDescription(nameof(SR.GridPanelRowsDescr))]
    [SRCategory(nameof(SR.CatLayout))]
    [DefaultValue(0)]
    [Localizable(true)]
    public int RowCount
    {
        get => _tableLayoutSettings.RowCount;
        set => _tableLayoutSettings.RowCount = value;
    }

    [SRDescription(nameof(SR.GridPanelRowStylesDescr))]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    [SRCategory(nameof(SR.CatLayout))]
    [DisplayName("Rows")]
    [MergableProperty(false)]
    [Browsable(false)]
    public TableLayoutRowStyleCollection RowStyles => _tableLayoutSettings.RowStyles;

    [SRDescription(nameof(SR.GridPanelColumnStylesDescr))]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    [SRCategory(nameof(SR.CatLayout))]
    [DisplayName("Columns")]
    [Browsable(false)]
    [MergableProperty(false)]
    public TableLayoutColumnStyleCollection ColumnStyles => _tableLayoutSettings.ColumnStyles;

    [EditorBrowsable(EditorBrowsableState.Advanced)]
    protected override ControlCollection CreateControlsInstance() => new TableLayoutControlCollection(this);

    private bool ShouldSerializeControls()
    {
        TableLayoutControlCollection collection = Controls;
        return collection is not null && collection.Count > 0;
    }

    #region Extended Properties
    bool IExtenderProvider.CanExtend(object obj) =>
        obj is Control control && control.Parent == this;

    [SRDescription(nameof(SR.GridPanelGetColumnSpanDescr))]
    [DefaultValue(1)]
    [SRCategory(nameof(SR.CatLayout))]
    [DisplayName("ColumnSpan")]
    public int GetColumnSpan(Control control) =>
        _tableLayoutSettings.GetColumnSpan(control);

    public void SetColumnSpan(Control control, int value)
    {
        // layout.SetColumnSpan() throws ArgumentException if out of range.
        _tableLayoutSettings.SetColumnSpan(control, value);
        Debug.Assert(GetColumnSpan(control) == value, "GetColumnSpan should be the same as we set it");
    }

    [SRDescription(nameof(SR.GridPanelGetRowSpanDescr))]
    [DefaultValue(1)]
    [SRCategory(nameof(SR.CatLayout))]
    [DisplayName("RowSpan")]
    public int GetRowSpan(Control control) => _tableLayoutSettings.GetRowSpan(control);

    public void SetRowSpan(Control control, int value)
    {
        // layout.SetRowSpan() throws ArgumentException if out of range.
        _tableLayoutSettings.SetRowSpan(control, value);
        Debug.Assert(GetRowSpan(control) == value, "GetRowSpan should be the same as we set it");
    }

    // get the row position of the control
    [DefaultValue(-1)]  // if change this value, also change the SerializeViaAdd in TableLayoutControlCollectionCodeDomSerializer
    [SRDescription(nameof(SR.GridPanelRowDescr))]
    [SRCategory(nameof(SR.CatLayout))]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
    [DisplayName("Row")]
    public int GetRow(Control control) => _tableLayoutSettings.GetRow(control);

    // set the row position of the control
    public void SetRow(Control control, int row)
    {
        _tableLayoutSettings.SetRow(control, row);
        Debug.Assert(GetRow(control) == row, "GetRow should be the same as we set it");
    }

    // get the row and column position of the control
    [DefaultValue(typeof(TableLayoutPanelCellPosition), "-1,-1")]  // if change this value, also change the SerializeViaAdd in TableLayoutControlCollectionCodeDomSerializer
    [SRDescription(nameof(SR.GridPanelCellPositionDescr))]
    [SRCategory(nameof(SR.CatLayout))]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
    [DisplayName("Cell")]
    public TableLayoutPanelCellPosition GetCellPosition(Control control) =>
        _tableLayoutSettings.GetCellPosition(control);

    // set the row and column of the control
    public void SetCellPosition(Control control, TableLayoutPanelCellPosition position) =>
        _tableLayoutSettings.SetCellPosition(control, position);

    // get the column position of the control
    [DefaultValue(-1)]  // if change this value, also change the SerializeViaAdd in TableLayoutControlCollectionCodeDomSerializer
    [SRDescription(nameof(SR.GridPanelColumnDescr))]
    [SRCategory(nameof(SR.CatLayout))]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
    [DisplayName("Column")]
    public int GetColumn(Control control) => _tableLayoutSettings.GetColumn(control);

    // set the column position of the control
    public void SetColumn(Control control, int column)
    {
        _tableLayoutSettings.SetColumn(control, column);
        Debug.Assert(GetColumn(control) == column, "GetColumn should be the same as we set it");
    }

    /// <summary>
    ///  get the control which covers the specified row and column. return null if we can't find one
    /// </summary>
    public Control? GetControlFromPosition(int column, int row) =>
        (Control?)_tableLayoutSettings.GetControlFromPosition(column, row);

    public TableLayoutPanelCellPosition GetPositionFromControl(Control? control) =>
        _tableLayoutSettings.GetPositionFromControl(control);

    /// <summary>
    ///  This returns an array representing the widths (in pixels) of the columns in the TableLayoutPanel.
    /// </summary>
    [Browsable(false)]
    [EditorBrowsable(EditorBrowsableState.Never)]
    public int[] GetColumnWidths()
    {
        TableLayout.ContainerInfo containerInfo = TableLayout.GetContainerInfo(this);
        if (containerInfo.Columns is null)
        {
            return [];
        }

        int[] cw = new int[containerInfo.Columns.Length];
        for (int i = 0; i < containerInfo.Columns.Length; i++)
        {
            cw[i] = containerInfo.Columns[i].MinSize;
        }

        return cw;
    }

    /// <summary>
    ///  This returns an array representing the heights (in pixels) of the rows in the TableLayoutPanel.
    /// </summary>
    [Browsable(false)]
    [EditorBrowsable(EditorBrowsableState.Never)]
    public int[] GetRowHeights()
    {
        TableLayout.ContainerInfo containerInfo = TableLayout.GetContainerInfo(this);
        if (containerInfo.Rows is null)
        {
            return [];
        }

        int[] rh = new int[containerInfo.Rows.Length];
        for (int i = 0; i < containerInfo.Rows.Length; i++)
        {
            rh[i] = containerInfo.Rows[i].MinSize;
        }

        return rh;
    }

    #endregion

    #region PaintCode

    [SRCategory(nameof(SR.CatAppearance))]
    [SRDescription(nameof(SR.TableLayoutPanelOnPaintCellDescr))]
    public event TableLayoutCellPaintEventHandler? CellPaint
    {
        add => Events.AddHandler(s_eventCellPaint, value);
        remove => Events.RemoveHandler(s_eventCellPaint, value);
    }

    /// <summary>
    ///  When a layout fires, make sure we're painting all of our
    ///  cell borders.
    /// </summary>
    [EditorBrowsable(EditorBrowsableState.Advanced)]
    protected override void OnLayout(LayoutEventArgs levent)
    {
        base.OnLayout(levent);
        Invalidate();
    }

    protected virtual void OnCellPaint(TableLayoutCellPaintEventArgs e)
    {
        ((TableLayoutCellPaintEventHandler?)Events[s_eventCellPaint])?.Invoke(this, e);
    }

    protected override void OnPaintBackground(PaintEventArgs e)
    {
        base.OnPaintBackground(e);

        // paint borderstyles on top of the background image in WM_ERASEBKGND

        int cellBorderWidth = CellBorderWidth;
        TableLayout.ContainerInfo containerInfo = TableLayout.GetContainerInfo(this);
        TableLayout.Strip[] colStrips = containerInfo.Columns;
        TableLayout.Strip[] rowStrips = containerInfo.Rows;
        TableLayoutPanelCellBorderStyle cellBorderStyle = CellBorderStyle;

        if (colStrips is null || rowStrips is null)
        {
            return;
        }

        int cols = colStrips.Length;
        int rows = rowStrips.Length;

        int totalColumnWidths = 0, totalColumnHeights = 0;

        Rectangle displayRect = DisplayRectangle;
        Rectangle clipRect = e.ClipRectangle;

        Graphics g = e.GraphicsInternal;

        // Leave the space for the border
        int startx;
        bool isRTL = RightToLeft == RightToLeft.Yes;
        if (isRTL)
        {
            startx = displayRect.Right - (cellBorderWidth / 2);
        }
        else
        {
            startx = displayRect.X + (cellBorderWidth / 2);
        }

        for (int i = 0; i < cols; i++)
        {
            int starty = displayRect.Y + (cellBorderWidth / 2);

            if (isRTL)
            {
                startx -= colStrips[i].MinSize;
            }

            for (int j = 0; j < rows; j++)
            {
                Rectangle outsideCellBounds = new(
                    startx,
                    starty,
                    colStrips[i].MinSize,
                    rowStrips[j].MinSize);

                Rectangle insideCellBounds = new(
                    outsideCellBounds.X + (cellBorderWidth + 1) / 2,
                    outsideCellBounds.Y + (cellBorderWidth + 1) / 2,
                    outsideCellBounds.Width - (cellBorderWidth + 1) / 2,
                    outsideCellBounds.Height - (cellBorderWidth + 1) / 2);

                if (clipRect.IntersectsWith(insideCellBounds))
                {
                    // First, call user's painting code
                    using (TableLayoutCellPaintEventArgs pcea = new(e, clipRect, insideCellBounds, i, j))
                    {
                        OnCellPaint(pcea);
                        if (!((IGraphicsHdcProvider)pcea).IsGraphicsStateClean)
                        {
                            // The Graphics object got touched, hit the public property on our original args
                            // to mark it as dirty as well.

                            g = e.Graphics;
                        }
                    }

                    // Paint the table border on top.
                    ControlPaint.PaintTableCellBorder(cellBorderStyle, g, outsideCellBounds);
                }

                starty += rowStrips[j].MinSize;

                // Only sum this up once...
                if (i == 0)
                {
                    totalColumnHeights += rowStrips[j].MinSize;
                }
            }

            if (!isRTL)
            {
                startx += colStrips[i].MinSize;
            }

            totalColumnWidths += colStrips[i].MinSize;
        }

        if (!HScroll && !VScroll && cellBorderStyle != TableLayoutPanelCellBorderStyle.None)
        {
            // Paint the border of the table if we are not auto scrolling.

            Rectangle tableBounds = new(
                cellBorderWidth / 2 + displayRect.X,
                cellBorderWidth / 2 + displayRect.Y,
                displayRect.Width - cellBorderWidth,
                displayRect.Height - cellBorderWidth);

            // If the borderStyle is Inset or Outset, we can only paint the lower bottom half since otherwise we
            // will have 1 pixel loss at the border.
            if (cellBorderStyle == TableLayoutPanelCellBorderStyle.Inset)
            {
                g.DrawLine(
                    SystemPens.ControlDark,
                    tableBounds.Right,
                    tableBounds.Y,
                    tableBounds.Right,
                    tableBounds.Bottom);

                g.DrawLine(
                    SystemPens.ControlDark,
                    tableBounds.X,
                    tableBounds.Y + tableBounds.Height - 1,
                    tableBounds.X + tableBounds.Width - 1,
                    tableBounds.Y + tableBounds.Height - 1);
            }
            else if (cellBorderStyle == TableLayoutPanelCellBorderStyle.Outset)
            {
                g.DrawLine(
                    SystemPens.Window,
                    tableBounds.X + tableBounds.Width - 1,
                    tableBounds.Y,
                    tableBounds.X + tableBounds.Width - 1,
                    tableBounds.Y + tableBounds.Height - 1);
                g.DrawLine(
                    SystemPens.Window,
                    tableBounds.X,
                    tableBounds.Y + tableBounds.Height - 1,
                    tableBounds.X + tableBounds.Width - 1,
                    tableBounds.Y + tableBounds.Height - 1);
            }
            else
            {
                ControlPaint.PaintTableCellBorder(cellBorderStyle, g, tableBounds);
            }

            ControlPaint.PaintTableControlBorder(cellBorderStyle, g, displayRect);
        }
        else
        {
            ControlPaint.PaintTableControlBorder(cellBorderStyle, g, displayRect);
        }
    }

    [EditorBrowsable(EditorBrowsableState.Never)]
    protected override void ScaleCore(float dx, float dy)
    {
        base.ScaleCore(dx, dy);
        ScaleAbsoluteStyles(new SizeF(dx, dy));
    }

    /// <summary>
    ///  Scale this form.  Form overrides this to enforce a maximum / minimum size.
    /// </summary>
    protected override void ScaleControl(SizeF factor, BoundsSpecified specified)
    {
        base.ScaleControl(factor, specified);
        ScaleAbsoluteStyles(factor);
    }

    private void ScaleAbsoluteStyles(SizeF factor)
    {
        TableLayout.ContainerInfo containerInfo = TableLayout.GetContainerInfo(this);
        int i = 0;

        // The last row/column can be larger than the
        // absolutely styled column width.
        int lastRowHeight = -1;
        int lastRow = containerInfo.Rows.Length - 1;
        if (containerInfo.Rows.Length > 0)
        {
            lastRowHeight = containerInfo.Rows[lastRow].MinSize;
        }

        int lastColumnHeight = -1;
        int lastColumn = containerInfo.Columns.Length - 1;
        if (containerInfo.Columns.Length > 0)
        {
            lastColumnHeight = containerInfo.Columns[^1].MinSize;
        }

        foreach (ColumnStyle cs in ColumnStyles)
        {
            if (cs.SizeType == SizeType.Absolute)
            {
                if (i == lastColumn && lastColumnHeight > 0)
                {
                    // the last column is typically expanded to fill the table. use the actual
                    // width in this case.
                    cs.Width = (float)Math.Round(lastColumnHeight * factor.Width);
                }
                else
                {
                    cs.Width = (float)Math.Round(cs.Width * factor.Width);
                }
            }

            i++;
        }

        i = 0;

        foreach (RowStyle rs in RowStyles)
        {
            if (rs.SizeType == SizeType.Absolute)
            {
                if (i == lastRow && lastRowHeight > 0)
                {
                    // the last row is typically expanded to fill the table. use the actual
                    // width in this case.
                    rs.Height = (float)Math.Round(lastRowHeight * factor.Height);
                }
                else
                {
                    rs.Height = (float)Math.Round(rs.Height * factor.Height);
                }
            }
        }
    }

    #endregion
}
